By Janice Harayda
“Based on a true story” often masks weaknesses in a plot. It may mean: “Hey, don’t blame us! It really happened that way.” A case in point is Stagecoach Sal, an attractive picture book “inspired” by the life of the first woman to carry the U.S. mail by stagecoach in California.

Deborah Hopkinson drew on promising historical material for her tale of a rifle-loving girl who thwarts a bandit intent on stealing the mail she carries on her stagecoach. But the plot doesn’t entirely make sense. Young Sal gets a clear warning from her parents before she sets out alone on a stagecoach to deliver mail: “No passengers!” Sal ignores this sensible advice when accosted at a remote spot by a man she recognizes as a famous poetry-spouting bandit. Instead of driving away, she invites the stranger to ride shotgun on her stagecoach. And you’re never sure why, when she has horses and the man seems to have none: Did she have a rebellious streak? Too much faith in her reputation as “a crack shot”? A misplaced desire to help?

Sal distracts the bandit from his desire to rob her by singing songs, Scheherazade-like, as they ride: “Polly Wolly Doodle,” “Sweet Betsy From Pike,” “She’ll Be Comin’ Round the Mountain” and “Shoo Fly, Don’t Bother Me!” Hopkinson integrates these toe-tappers well into her story. And given the gaps in her plot, the songs – and Carson Ellis’s warm and lively pictures – account for much of the appeal of the book. Stagecoach Sal is no Brave Irene, William Steig’s tale of a girl who plunges into snowstorm to deliver a dress made by her seamstress mother, a book that beautifully evokes its young heroine’s character and struggle. But Hopkinson and Eliis offer an easygoing introduction to several classic folksongs that many children know less well than “Baby Beluga.” And leaky plot ultimately may count for less than the fun of singing at bedtime, “Oh, I went down South / for to see my Sal / singing Polly wolly doodle all the day.”

Best line/picture: Ellis’s fine illustrations include nice touches such as a compass at the bottom of one page, a pig tied to a covered wagon on another.

Worst line/picture: Hopkinson says in an afterword that you can hear “some of Sal’s favorite songs” on the Kids’ Pages of the National Institute of Environmental Health Sciences. True, but frustration awaits anyone who reads that “some” as “all.” I couldn’t find “Sweet Betsy From Pike” after many searches of the recommended site using varied spellings of Betsy, quotations from the lyrics and more. Eventually the lyrics and part of the music on turned up on Wikipedia.

You can also follow Jan Harayda (@janiceharayda) on Twitter at www.twitter.com/janiceharayda. She satirizes American literary culture, such as is its, on her Fake Book News page on Twitter (@FakeBookNews).